Wednesday 3 May 2023

‘Climate change could reduce deep sea life by 40%’

Life in the deepest parts of the world’s oceans could drop by 40% due to climate change.

That’s according to a study by the University of Exeter, claiming that this reduction could take place as soon as 2100.

The twilight zone is the area under threat, which represents the area spanning from 200m to 1,000m below the surface.

In warmer periods of history, the number of lifeforms thriving in this area dropped dramatically, the scientists said – analysing data from 50 million and 15 million years ago.

The reason for the decline is with hotter temperatures bacteria consume food quicker, which led to less sustenance reaching the depths of the ocean.

This twilight zone is home to more marine life than the rest of the ocean combined – including phytoplankton and microbes.

Based on current temperatures and estimations of how they may increase, the researchers found that the impact will not be good for the wildlife and may have already even started to occur.

Dr Katherine Crichton, lead author, said: “The rich variety of twilight zone life evolved in the last few million years, when ocean waters had cooled enough to act rather like a fridge, preserving the food for longer and improving conditions; allowing life to thrive.

“Our study is a first step to finding out how vulnerable this ocean habitat may be to climate warming. Unless we rapidly reduce greenhouse gas emissions, this could lead to the disappearance or extinction of much twilight zone life within 150 years, with effects spanning millennia thereafter.”